From 111eec5b6186ab69def2daf7e04c7ef2a167d6a6 Mon Sep 17 00:00:00 2001 From: Cesar Descalzo Blanco Date: Fri, 8 Mar 2024 11:31:53 +0100 Subject: [PATCH 1/7] Co-authored-by: Cesar Descalzo Blanco MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove unnecessary `PhantomData` Co-authored-by: Antonio Mejías Gil Progress until 08/03 Co-authored-by: Antonio Mejías Gil constructing range check, wip working on padding println nightmare, issue apparently fixed Remove redundant padding. Fix import. code cleanup further cleanup found better way to fix padding the 'better way' to fix padding actually broke other tests - reverted This reverts commit d4727ba905065c3f5662699d48c2efb0a3e87feb. moved example to examples folder, refactored, tested many cases --- README.md | 6 +- examples/less_than.rs | 138 ++++++++++++++++++++++++++++++++++++++++++ src/lib.rs | 11 ++-- src/spartan/snark.rs | 28 +++++++++ 4 files changed, 175 insertions(+), 8 deletions(-) create mode 100644 examples/less_than.rs diff --git a/README.md b/README.md index 2986250..66b57a7 100644 --- a/README.md +++ b/README.md @@ -31,4 +31,8 @@ This project may contain trademarks or logos for projects, products, or services trademarks or logos is subject to and must follow [Microsoft's Trademark & Brand Guidelines](https://www.microsoft.com/en-us/legal/intellectualproperty/trademarks/usage/general). Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. -Any use of third-party trademarks or logos are subject to those third-party's policies. \ No newline at end of file +Any use of third-party trademarks or logos are subject to those third-party's policies. + +## Examples + +Run `cargo run --example EXAMPLE_NAME` to run the corresponding example. Leave `EXAMPLE_NAME` empty for a list of available examples. diff --git a/examples/less_than.rs b/examples/less_than.rs new file mode 100644 index 0000000..2f8a173 --- /dev/null +++ b/examples/less_than.rs @@ -0,0 +1,138 @@ +use bellpepper_core::{ + boolean::AllocatedBit, num::AllocatedNum, Circuit, ConstraintSystem, LinearCombination, + SynthesisError, +}; +use ff::{PrimeField, PrimeFieldBits}; +use spartan2::{ + errors::SpartanError, + traits::{snark::RelaxedR1CSSNARKTrait, Group}, + SNARK, +}; + +fn num_to_bits_le_bounded>( + cs: &mut CS, + n: AllocatedNum, + num_bits: u8, +) -> Result, SynthesisError> { + let opt_bits = match n.get_value() { + Some(v) => v + .to_le_bits() + .into_iter() + .take(num_bits as usize) + .map(|b| Some(b)) + .collect::>>(), + None => vec![None; num_bits as usize], + }; + + // Add one witness per input bit in little-endian bit order + let bits_circuit = opt_bits.into_iter() + .enumerate() + // AllocateBit enforces the value to be 0 or 1 at the constraint level + .map(|(i, b)| AllocatedBit::alloc(cs.namespace(|| format!("b_{}", i)), b).unwrap()) + .collect::>(); + + let mut weighted_sum_lc = LinearCombination::zero(); + let mut pow2 = F::ONE; + + for bit in bits_circuit.iter() { + weighted_sum_lc = weighted_sum_lc + (pow2, bit.get_variable()); + pow2 = pow2.double(); + } + + cs.enforce( + || "bit decomposition check", + |lc| lc + &weighted_sum_lc, + |lc| lc + CS::one(), + |lc| lc + n.get_variable(), + ); + + Ok(bits_circuit) +} + +// Range check: constrains input < `bound`. The bound must fit into +// `num_bits` bits (this is asserted in the circuit constructor). +// Important: it must be checked elsewhere that the input fits into +// `num_bits` bits - this is NOT constrained by this circuit in order to +// avoid duplications (hence "unsafe") +#[derive(Clone, Debug)] +struct LessThanCircuitUnsafe { + bound: u64, // Will be a constant in the constraits, not a variable + input: u64, // Will be an input/output variable + num_bits: u8, +} + +impl LessThanCircuitUnsafe { + fn new(bound: u64, input: u64, num_bits: u8) -> Self { + assert!(bound < (1 << num_bits)); + Self { + bound, + input, + num_bits, + } + } +} + +impl Circuit for LessThanCircuitUnsafe { + fn synthesize>(self, cs: &mut CS) -> Result<(), SynthesisError> { + assert!(F::NUM_BITS > self.num_bits as u32 + 1); + + let input = AllocatedNum::alloc(cs.namespace(|| "input"), || Ok(F::from(self.input)))?; + + let shifted_diff = AllocatedNum::alloc(cs.namespace(|| "shifted_diff"), || { + Ok(F::from(self.input + (1 << self.num_bits) - self.bound)) + })?; + + cs.enforce( + || "shifted_diff_computation", + |lc| lc + input.get_variable() + (F::from((1 << self.num_bits) - self.bound), CS::one()), + |lc| lc + CS::one(), + |lc| lc + shifted_diff.get_variable(), + ); + + let shifted_diff_bits = num_to_bits_le_bounded::(cs, shifted_diff, self.num_bits + 1)?; + + // Check that the last (i.e. most sifnificant) bit is 0 + cs.enforce( + || "bound_check", + |lc| lc + shifted_diff_bits[self.num_bits as usize].get_variable(), + |lc| lc + CS::one(), + |lc| lc + (F::ZERO, CS::one()), + ); + + Ok(()) + } +} + +fn verify_circuit>( + bound: u64, + input: u64, + num_bits: u8, +) -> Result<(), SpartanError> { + let circuit = LessThanCircuitUnsafe::new(bound, input, num_bits); + + // produce keys + let (pk, vk) = SNARK::::setup(circuit.clone()).unwrap(); + + // produce a SNARK + let snark = SNARK::prove(&pk, circuit).unwrap(); + + // verify the SNARK + snark.verify(&vk, &[]) +} + +fn main() { + type G = pasta_curves::pallas::Point; + type EE = spartan2::provider::ipa_pc::EvaluationEngine; + type S = spartan2::spartan::snark::RelaxedR1CSSNARK; + + // Typical exapmle, ok + assert!(verify_circuit::(17, 9, 10).is_ok()); + // Typical example, err + assert!(verify_circuit::(17, 20, 10).is_err()); + // Edge case, err + assert!(verify_circuit::(4, 4, 10).is_err()); + // Edge case, ok + assert!(verify_circuit::(4, 3, 10).is_ok()); + // Minimum number of bits, ok + assert!(verify_circuit::(4, 3, 3).is_ok()); +} diff --git a/src/lib.rs b/src/lib.rs index 5a60502..b55f0f0 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -76,6 +76,7 @@ impl, C: Circuit> SNARK Result<(ProverKey, VerifierKey), SpartanError> { let (pk, vk) = S::setup(circuit)?; + Ok((ProverKey { pk }, VerifierKey { vk })) } @@ -108,15 +109,12 @@ mod tests { use super::*; use crate::provider::{bn256_grumpkin::bn256, secp_secq::secp256k1}; use bellpepper_core::{num::AllocatedNum, ConstraintSystem, SynthesisError}; - use core::marker::PhantomData; use ff::PrimeField; #[derive(Clone, Debug, Default)] - struct CubicCircuit { - _p: PhantomData, - } + struct CubicCircuit {} - impl Circuit for CubicCircuit + impl Circuit for CubicCircuit where F: PrimeField, { @@ -178,8 +176,7 @@ mod tests { let circuit = CubicCircuit::default(); // produce keys - let (pk, vk) = - SNARK::::Scalar>>::setup(circuit.clone()).unwrap(); + let (pk, vk) = SNARK::::setup(circuit.clone()).unwrap(); // produce a SNARK let res = SNARK::prove(&pk, circuit); diff --git a/src/spartan/snark.rs b/src/spartan/snark.rs index a1ad696..8520650 100644 --- a/src/spartan/snark.rs +++ b/src/spartan/snark.rs @@ -101,6 +101,26 @@ impl> RelaxedR1CSSNARKTrait for Relaxe ) -> Result<(Self::ProverKey, Self::VerifierKey), SpartanError> { let mut cs: ShapeCS = ShapeCS::new(); let _ = circuit.synthesize(&mut cs); + + // Padding the ShapeCS: constraints (rows) and variables (columns) + let num_constraints = cs.num_constraints(); + + (num_constraints..num_constraints.next_power_of_two()).for_each(|i| { + cs.enforce( + || format!("padding_constraint_{i}"), + |lc| lc, + |lc| lc, + |lc| lc, + ) + }); + + let num_vars = cs.num_aux(); + + (num_vars..num_vars.next_power_of_two()).for_each(|i| { + cs.alloc(|| format!("padding_var_{i}"), || Ok(G::Scalar::ZERO)) + .unwrap(); + }); + let (S, ck) = cs.r1cs_shape(); let (pk_ee, vk_ee) = EE::setup(&ck); @@ -121,6 +141,14 @@ impl> RelaxedR1CSSNARKTrait for Relaxe let mut cs: SatisfyingAssignment = SatisfyingAssignment::new(); let _ = circuit.synthesize(&mut cs); + // Padding variables + let num_vars = cs.aux_slice().len(); + + (num_vars..num_vars.next_power_of_two()).for_each(|i| { + cs.alloc(|| format!("padding_var_{i}"), || Ok(G::Scalar::ZERO)) + .unwrap(); + }); + let (u, w) = cs .r1cs_instance_and_witness(&pk.S, &pk.ck) .map_err(|_e| SpartanError::UnSat)?; From a88763f0ef76a341ddc53ab710277e809940bc55 Mon Sep 17 00:00:00 2001 From: Cesar Descalzo Blanco Date: Fri, 15 Mar 2024 11:28:27 +0100 Subject: [PATCH 2/7] Add LessThanCircuitSafe example. Pass arguments as field elements instead of unsigned integers. --- examples/less_than.rs | 128 ++++++++++++++++++++++++++++++++++-------- 1 file changed, 106 insertions(+), 22 deletions(-) diff --git a/examples/less_than.rs b/examples/less_than.rs index 2f8a173..973f5f7 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -3,6 +3,7 @@ use bellpepper_core::{ SynthesisError, }; use ff::{PrimeField, PrimeFieldBits}; +use pasta_curves::Fq; use spartan2::{ errors::SpartanError, traits::{snark::RelaxedR1CSSNARKTrait, Group}, @@ -49,21 +50,32 @@ fn num_to_bits_le_bounded(n: F) -> u8 { + let bits = n.to_le_bits(); + let mut msb_index = 0; + for (i, b) in bits.iter().enumerate() { + if *b { + msb_index = i as u8; + } + } + msb_index +} + // Range check: constrains input < `bound`. The bound must fit into // `num_bits` bits (this is asserted in the circuit constructor). // Important: it must be checked elsewhere that the input fits into // `num_bits` bits - this is NOT constrained by this circuit in order to // avoid duplications (hence "unsafe") #[derive(Clone, Debug)] -struct LessThanCircuitUnsafe { - bound: u64, // Will be a constant in the constraits, not a variable - input: u64, // Will be an input/output variable +struct LessThanCircuitUnsafe { + bound: F, // Will be a constant in the constraits, not a variable + input: F, // Will be an input/output variable num_bits: u8, } -impl LessThanCircuitUnsafe { - fn new(bound: u64, input: u64, num_bits: u8) -> Self { - assert!(bound < (1 << num_bits)); +impl LessThanCircuitUnsafe { + fn new(bound: F, input: F, num_bits: u8) -> Self { + assert!(get_msb_index(bound) < num_bits); Self { bound, input, @@ -72,20 +84,20 @@ impl LessThanCircuitUnsafe { } } -impl Circuit for LessThanCircuitUnsafe { +impl Circuit for LessThanCircuitUnsafe { fn synthesize>(self, cs: &mut CS) -> Result<(), SynthesisError> { assert!(F::NUM_BITS > self.num_bits as u32 + 1); - let input = AllocatedNum::alloc(cs.namespace(|| "input"), || Ok(F::from(self.input)))?; + let input = AllocatedNum::alloc(cs.namespace(|| "input"), || Ok(self.input))?; let shifted_diff = AllocatedNum::alloc(cs.namespace(|| "shifted_diff"), || { - Ok(F::from(self.input + (1 << self.num_bits) - self.bound)) + Ok(self.input + F::from(1 << self.num_bits) - self.bound) })?; cs.enforce( || "shifted_diff_computation", - |lc| lc + input.get_variable() + (F::from((1 << self.num_bits) - self.bound), CS::one()), - |lc| lc + CS::one(), + |lc| lc + input.get_variable() + (F::from(1 << self.num_bits) - self.bound, CS::one()), + |lc: LinearCombination| lc + CS::one(), |lc| lc + shifted_diff.get_variable(), ); @@ -103,15 +115,70 @@ impl Circuit for LessThanCircuitUnsafe { } } -fn verify_circuit>( - bound: u64, - input: u64, +#[derive(Clone, Debug)] +struct LessThanCircuitSafe { + bound: F, + input: F, + num_bits: u8, +} + +impl LessThanCircuitSafe { + fn new(bound: F, input: F, num_bits: u8) -> Self { + assert!(get_msb_index(bound) < num_bits); + Self { + bound, + input, + num_bits, + } + } +} + +impl Circuit for LessThanCircuitSafe { + fn synthesize>(self, cs: &mut CS) -> Result<(), SynthesisError> { + let input = AllocatedNum::alloc(cs.namespace(|| "input"), || Ok(self.input))?; + + // Perform the input bit decomposition check + num_to_bits_le_bounded::(cs, input, self.num_bits)?; + + // Entering a new namespace to prefix variables in the + // LessThanCircuitUnsafe, thus avoiding name clashes + cs.push_namespace(|| "less_than_safe"); + + LessThanCircuitUnsafe { + bound: self.bound, + input: self.input, + num_bits: self.num_bits, + } + .synthesize(cs) + } +} + +fn verify_circuit_unsafe>( + bound: G::Scalar, + input: G::Scalar, num_bits: u8, ) -> Result<(), SpartanError> { let circuit = LessThanCircuitUnsafe::new(bound, input, num_bits); // produce keys - let (pk, vk) = SNARK::::setup(circuit.clone()).unwrap(); + let (pk, vk) = SNARK::>::setup(circuit.clone()).unwrap(); + + // produce a SNARK + let snark = SNARK::prove(&pk, circuit).unwrap(); + + // verify the SNARK + snark.verify(&vk, &[]) +} + +fn verify_circuit_safe>( + bound: G::Scalar, + input: G::Scalar, + num_bits: u8, +) -> Result<(), SpartanError> { + let circuit = LessThanCircuitSafe::new(bound, input, num_bits); + + // produce keys + let (pk, vk) = SNARK::>::setup(circuit.clone()).unwrap(); // produce a SNARK let snark = SNARK::prove(&pk, circuit).unwrap(); @@ -125,14 +192,31 @@ fn main() { type EE = spartan2::provider::ipa_pc::EvaluationEngine; type S = spartan2::spartan::snark::RelaxedR1CSSNARK; - // Typical exapmle, ok - assert!(verify_circuit::(17, 9, 10).is_ok()); + println!("Executing unsafe circuit..."); + //Typical example, ok + assert!(verify_circuit_unsafe::(Fq::from(17u64), Fq::from(9u64), 10).is_ok()); + // Typical example, err + assert!(verify_circuit_unsafe::(Fq::from(17u64), Fq::from(20u64), 10).is_err()); + // Edge case, err + assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(4u64), 10).is_err()); + // Edge case, ok + assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); + // Minimum number of bits for the bound, ok + assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); + // Insufficient number of bits for the input, ok + assert!(verify_circuit_unsafe::(Fq::from(4u64), -Fq::one(), 3).is_ok()); + + println!("Executing safe circuit..."); + // Typical example, ok + assert!(verify_circuit_safe::(Fq::from(17u64), Fq::from(9u64), 10).is_ok()); // Typical example, err - assert!(verify_circuit::(17, 20, 10).is_err()); + assert!(verify_circuit_safe::(Fq::from(17u64), Fq::from(20u64), 10).is_err()); // Edge case, err - assert!(verify_circuit::(4, 4, 10).is_err()); + assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(4u64), 10).is_err()); // Edge case, ok - assert!(verify_circuit::(4, 3, 10).is_ok()); - // Minimum number of bits, ok - assert!(verify_circuit::(4, 3, 3).is_ok()); + assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); + // Minimum number of bits for the bound, ok + assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); + // Insufficient number of bits for the input, err + assert!(verify_circuit_safe::(Fq::from(4u64), -Fq::one(), 3).is_err()); } From 7f84d287103a18dad4d612e3b6377fc2a5d70aa6 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Antonio=20Mej=C3=ADas=20Gil?= Date: Fri, 15 Mar 2024 11:41:00 +0100 Subject: [PATCH 3/7] added some documentation --- examples/less_than.rs | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/examples/less_than.rs b/examples/less_than.rs index 973f5f7..6d5a0b9 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -63,9 +63,10 @@ fn get_msb_index(n: F) -> u8 { // Range check: constrains input < `bound`. The bound must fit into // `num_bits` bits (this is asserted in the circuit constructor). -// Important: it must be checked elsewhere that the input fits into -// `num_bits` bits - this is NOT constrained by this circuit in order to -// avoid duplications (hence "unsafe") +// Important: it must be checked elsewhere (in an overarching circuit) that the +// input fits into `num_bits` bits - this is NOT constrained by this circuit +// in order to avoid duplications (hence "unsafe"). Cf. LessThanCircuitSafe for +// a safe version. #[derive(Clone, Debug)] struct LessThanCircuitUnsafe { bound: F, // Will be a constant in the constraits, not a variable @@ -115,6 +116,10 @@ impl Circuit for LessThanCircuitUnsafe { } } +// Range check: constrains input < `bound`. The bound must fit into +// `num_bits` bits (this is asserted in the circuit constructor). +// Furthermore, the input must fit into `num_bits`, which is enforced at the +// constraint level. #[derive(Clone, Debug)] struct LessThanCircuitSafe { bound: F, @@ -203,7 +208,9 @@ fn main() { assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); // Minimum number of bits for the bound, ok assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); - // Insufficient number of bits for the input, ok + // Insufficient number of bits for the input, but this is not detected by the + // unsafety of the circuit (compare with the last example below) + // Note that -Fq::one() is corresponds to q - 1 > bound assert!(verify_circuit_unsafe::(Fq::from(4u64), -Fq::one(), 3).is_ok()); println!("Executing safe circuit..."); @@ -217,6 +224,8 @@ fn main() { assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); // Minimum number of bits for the bound, ok assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); - // Insufficient number of bits for the input, err + // Insufficient number of bits for the input, err (compare with the last example + // above). + // Note that -Fq::one() is corresponds to q - 1 > bound assert!(verify_circuit_safe::(Fq::from(4u64), -Fq::one(), 3).is_err()); } From 7cd65ad608c1717610f68e2256144243853ef864 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Antonio=20Mej=C3=ADas=20Gil?= Date: Fri, 15 Mar 2024 11:44:04 +0100 Subject: [PATCH 4/7] added message --- examples/less_than.rs | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/examples/less_than.rs b/examples/less_than.rs index 6d5a0b9..6cee258 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -213,6 +213,8 @@ fn main() { // Note that -Fq::one() is corresponds to q - 1 > bound assert!(verify_circuit_unsafe::(Fq::from(4u64), -Fq::one(), 3).is_ok()); + println!("Unsafe circuit OK"); + println!("Executing safe circuit..."); // Typical example, ok assert!(verify_circuit_safe::(Fq::from(17u64), Fq::from(9u64), 10).is_ok()); @@ -228,4 +230,6 @@ fn main() { // above). // Note that -Fq::one() is corresponds to q - 1 > bound assert!(verify_circuit_safe::(Fq::from(4u64), -Fq::one(), 3).is_err()); + + println!("Safe circuit OK"); } From f6725c8cc265bbf3eea5599bcb6f7535255857b9 Mon Sep 17 00:00:00 2001 From: Cesar Descalzo Blanco Date: Fri, 15 Mar 2024 13:04:54 +0100 Subject: [PATCH 5/7] Remove unnecesary u64 hints. Cleanup get_msb_index. --- examples/less_than.rs | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/examples/less_than.rs b/examples/less_than.rs index 6cee258..9d5e3a8 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -51,14 +51,13 @@ fn num_to_bits_le_bounded(n: F) -> u8 { - let bits = n.to_le_bits(); - let mut msb_index = 0; - for (i, b) in bits.iter().enumerate() { - if *b { - msb_index = i as u8; - } - } - msb_index + n.to_le_bits() + .into_iter() + .enumerate() + .rev() + .find(|(_, b)| *b) + .unwrap() + .0 as u8 } // Range check: constrains input < `bound`. The bound must fit into @@ -199,37 +198,37 @@ fn main() { println!("Executing unsafe circuit..."); //Typical example, ok - assert!(verify_circuit_unsafe::(Fq::from(17u64), Fq::from(9u64), 10).is_ok()); + assert!(verify_circuit_unsafe::(Fq::from(17), Fq::from(9), 10).is_ok()); // Typical example, err - assert!(verify_circuit_unsafe::(Fq::from(17u64), Fq::from(20u64), 10).is_err()); + assert!(verify_circuit_unsafe::(Fq::from(17), Fq::from(20), 10).is_err()); // Edge case, err - assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(4u64), 10).is_err()); + assert!(verify_circuit_unsafe::(Fq::from(4), Fq::from(4), 10).is_err()); // Edge case, ok - assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); + assert!(verify_circuit_unsafe::(Fq::from(4), Fq::from(3), 10).is_ok()); // Minimum number of bits for the bound, ok - assert!(verify_circuit_unsafe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); + assert!(verify_circuit_unsafe::(Fq::from(4), Fq::from(3), 3).is_ok()); // Insufficient number of bits for the input, but this is not detected by the // unsafety of the circuit (compare with the last example below) // Note that -Fq::one() is corresponds to q - 1 > bound - assert!(verify_circuit_unsafe::(Fq::from(4u64), -Fq::one(), 3).is_ok()); + assert!(verify_circuit_unsafe::(Fq::from(4), -Fq::one(), 3).is_ok()); println!("Unsafe circuit OK"); println!("Executing safe circuit..."); // Typical example, ok - assert!(verify_circuit_safe::(Fq::from(17u64), Fq::from(9u64), 10).is_ok()); + assert!(verify_circuit_safe::(Fq::from(17), Fq::from(9), 10).is_ok()); // Typical example, err - assert!(verify_circuit_safe::(Fq::from(17u64), Fq::from(20u64), 10).is_err()); + assert!(verify_circuit_safe::(Fq::from(17), Fq::from(20), 10).is_err()); // Edge case, err - assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(4u64), 10).is_err()); + assert!(verify_circuit_safe::(Fq::from(4), Fq::from(4), 10).is_err()); // Edge case, ok - assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 10).is_ok()); + assert!(verify_circuit_safe::(Fq::from(4), Fq::from(3), 10).is_ok()); // Minimum number of bits for the bound, ok - assert!(verify_circuit_safe::(Fq::from(4u64), Fq::from(3u64), 3).is_ok()); + assert!(verify_circuit_safe::(Fq::from(4), Fq::from(3), 3).is_ok()); // Insufficient number of bits for the input, err (compare with the last example // above). // Note that -Fq::one() is corresponds to q - 1 > bound - assert!(verify_circuit_safe::(Fq::from(4u64), -Fq::one(), 3).is_err()); + assert!(verify_circuit_safe::(Fq::from(4), -Fq::one(), 3).is_err()); println!("Safe circuit OK"); } From eb2843e26ff653d074ecaef5b1a47876e832f964 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Antonio=20Mej=C3=ADas=20Gil?= Date: Fri, 15 Mar 2024 15:33:47 +0100 Subject: [PATCH 6/7] fixed clippy warning --- examples/less_than.rs | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/examples/less_than.rs b/examples/less_than.rs index 9d5e3a8..9f4d3aa 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -20,7 +20,7 @@ fn num_to_bits_le_bounded>>(), None => vec![None; num_bits as usize], }; From 9c71a23156ac0bb4d34c7a05e99089940a22a915 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Antonio=20Mej=C3=ADas=20Gil?= Date: Mon, 18 Mar 2024 17:10:46 +0100 Subject: [PATCH 7/7] tweaked documentation --- examples/less_than.rs | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/examples/less_than.rs b/examples/less_than.rs index 9f4d3aa..a3bac59 100644 --- a/examples/less_than.rs +++ b/examples/less_than.rs @@ -60,8 +60,9 @@ fn get_msb_index(n: F) -> u8 { .0 as u8 } -// Range check: constrains input < `bound`. The bound must fit into -// `num_bits` bits (this is asserted in the circuit constructor). +// Constrains `input` < `bound`, where the LHS is a witness and the RHS is a +// constant. The bound must fit into `num_bits` bits (this is asserted in the +// circuit constructor). // Important: it must be checked elsewhere (in an overarching circuit) that the // input fits into `num_bits` bits - this is NOT constrained by this circuit // in order to avoid duplications (hence "unsafe"). Cf. LessThanCircuitSafe for @@ -115,8 +116,9 @@ impl Circuit for LessThanCircuitUnsafe { } } -// Range check: constrains input < `bound`. The bound must fit into -// `num_bits` bits (this is asserted in the circuit constructor). +// Constrains `input` < `bound`, where the LHS is a witness and the RHS is a +// constant. The bound must fit into `num_bits` bits (this is asserted in the +// circuit constructor). // Furthermore, the input must fit into `num_bits`, which is enforced at the // constraint level. #[derive(Clone, Debug)]